Petroleum products and natural gas in particular contain products which are undesirable for the purposes of transportation and/or handling.
Of these substances, one of the main constituents to be removed is water, which has proved to encourage the formation of hydrates and is conducive to corrosion. In practice, hydrates can cause transport pipelines to become clogged and blocked, preventing gas from passing through them in the long term, and the corrosive action of the gas causes deterioration in pipelines and processing installations. These two factors are extremely detrimental in terms of their consequences and can often lead to quite lengthy production stoppages because it is very difficult to break down any hydrates which have formed, incurring severe financial losses.
Various methods have been described in the prior art as a means of overcoming these disadvantages.
Patent FR 2.605.241 describes a method of treating natural gas spanning several stages performed in several devices in succession. In a first enclosure, the gas to be treated is brought into contact with a cooled physical solvent in order to produce a gas which is saturated with the added water from the solvent and this gas is then cooled in an exchanger in order to condense the aqueous phase containing the solvent and the saturation water as well as a phase of liquid hydrocarbons. The cooled, dehydrated gas and the fraction containing the condensed hydrocarbons are then separated in a separator unit.
This method has significant advantages as compared with the techniques used in the art. However, the methane and hydrocarbons such as propane as well as hydrocarbons with more than three carbon atoms are not fully separated.
In addition, it is necessary to use at least two devices, which requires additional space in the processing plants incurring the additional capital investment.